Railway switch and signal mechanism



(N o Model.) 3 Sheets-Sheet 1. I J. W. THOMAS, Jr.

. RAILWAY SWITCH AND SIGNAL MECHANISM. v No. 606,602. Patented June-Z8,1898.

(No Model.)

3 Sheets-Sheet 2. I J. W. THOMAS, Jr.

RAILWAY SWITCH AND SIGNAL MECHANISM} No. 606,602.

Patented June 28, 1898.

a sneetssheet 3.

'J. w. THOMAS, Jr.

(No Model!) RAILWAY SWITCH AND SIGNAL MECHANISM. N 6 Patented June 28,-1898.

2 a a: l 6 D y'hwssea 700W77zw/za5 the switch or signal lever itself.

PATENT OFFICE.

JOHN W. THOMAS, in, or NASH ILLE, TENNESSEE.

RAILWAY Tsw 'T c D s c Nat. M EC HAN lSM SPECIFICATION forming partgofLetters Patent No. 'eoaeoa, dated June 28,1898.

Application filed AprilZl, 18981 To all whom, it may concern:

Be it known that I, JOHN W. THOMAS, Jr., of Nashville,'Tennessee, haveinvented certain new and useful Improvements in Railway Switch andSignal Mechanism, of which the following is a specification.

My invention relates to railway switch and signal interlocking machines,and more particularly to that type of such machines in which preliminarylocking is employed. By preliminary locking I mean that the interlockingof the levers of the machine is effected, not by the movement of theswitch or signal lever itself, but by the movement of the latch-leverwith which each of suchde vers is provided and which must be firstmanipulated in order to release and permit the movement of the switch orsignal lever to which it is applied. In such a machine a link or rockeris used to transmit movement from thelatch to the tappets, flops, orlocking-bars, the interlocking between the levers of the unachine beingaccomplished by means of said tappets, flops, or locking-barsinconjunction with dogs of suitable form and construction,. as wellunderstood by those skilled in the art to which this invention relates.1 p

It is the main object of my invention to handle a double-plunger lockfor facin g-point switches from a mechanical interlocking machine bymeans of preliminarylocking, or, in other words, by means of the latchinstead of This has been done in the case of a single=plunger look; butI am notaware of any preliminary-locking mechanical interlockingmachine'fbyjwhich a double-plunger facing-point lock has been handled orwhich, in fact, is constructed and adapted to do this work. So far as Iam aware double-plunger facing-point looks, when employed at all, havebeen used inconj unction. with mechanical interlocking machines whichhave no preliminary locking as, for example,;the interlocking machinewhich is the subject of my Patent No. 468,160 of February 2,-1892. Thelink or rocker which I employ in this connection is also adapted for usein connection with a two-position signaloperatinglever or withslightmodification can be adapted for service in connection with athree-position signal-operating lever.

I shall first describe my improvements by I Serial No. 678,374. (Nomodel.)

' reference to the drawings accompanying and forming part of thisspecification, and will then point out in more particularity in theclaims those features which I believe to be "new and ofmy own invention.I

In the said drawings, Figure 1 is a plan of a portion-of a railway-trackin which the switch-points are combined with a doubleplunger lock inaccordance with my inventio n. Fig. 2 is a sectional side elevation ofthe interlocking machine-leverin the tower or cabin foroperating saidfacing-pointlock. Fig. 2 is a view of thelink block or pin detachedlFig. '3 is a plan'on enlarged scale of the double-plunger facing-pointlock in one of its locking positions. Fig. {i is a longitudinal centralsection of the same. Fig. 5 is a similar section representing the sideshifted, so as to bring it to the intermedial position, in which theswitch points are unlocked.

Fig. 6 is a cross-section of the device on'line b 6, Fig. 3. Fig. 7 isan enlarged elevation ofathe link or rocker forming part of themechanism shown in Fig. 2. of 'a slightly-modified form of said link.

A, Fig; 1, isa railway-track.

A is the facing-point switch, which through the usual connectionsindicated in part at a b c is connected to the appropriate switchleverof the interlocking machine in the tower.

To the switch points is connected the notched bar B, which extendsthrough and can slide back and forth. in a guide d in the base or bottomcastingv D of the look. This base or casting is secured in properposition alongside of the track and is provided with suitable guides, inwhich is supported the slide-barC: This slide-bar C at one end 1 isconnected through suitable intermediaries with the point-lock-operatinglever E, Fig. 2, of the interlocking machine in the tower, and itsopposite end 2 may be connected, as shown in Fig. 1, to the usualdetector-bar 3. Upon the under side of the slide-bar C are secured twolocking-lugs e j, which are so located that they are on opposite sidesof the notched bar B and in the plane of notches e f in said bar. Whenthe switch is thrownto one eX- treme of its movement, the notch e. willbe brought opposite to and'in register-with the lug 6, so that it may beentered by the latter, as shown in Figs. 3 and 4.. When the switch Fig.8 is a like View" is thrown to the opposite extreme, the notch f and thelugf will be brought into register. At each extreme of the movement ofthe slidebar C one or the other of the lugs c orf will engage itsappropriate notch c or f and then lock the notch-bar l3, andconsequently the switches. Vhen the slide-bar is in intermediateposition, as in Fig. 5, both lugs c andf will be out of engagement withthe notched bar and the latter, and consequently the switch will be freeto move.

The facing-point switeh-lock-operating leverE of the interlockingmachine represented in Fig. 2 is connected to the slide-bar C at 1 byintermediaries which are well known, and therefore require nodescription or illustration here. The latch-lever with which saidlock-operating lever is provided is shown at F. to the tappetj 0f theinterlocking mechanism by means of latch-rod 1, link block or pin h,(shown separately in side elevation in Fig. 2",) slotted link or rockerG, and connection 2'. The latch-rod g is provided with a lateralprojection g, which constitutes the latch proper and is intended toengage one of the notches 7: 7t 76 in the quadrant ll. A spring 8presses the latch-rod g and latch g in a direction to cause the latterto engage the quadrant. The latch-lever F lifts the rod g against thestress of spring .9.

The link G is pivoted at m to the frame of the machine and can rock uponthat pivot as a center. It is provided with a longitudinalslightly-curved slot'n. The headed link block or pin It extends throughand can move back and forth in and lengthwise of the slot in the linkand is attached to the lower end of the latch-rod g by a central boltlb. The link itself has in the lower edge of its slot and at a pointabout midway between the two ends of the same a gain or recess 1). Thisfeature is found in both forms of links, Figs. '7 and 8. The link inFig. 8 has in addition to the intermediate recess 1) a recess 1) at oneend and an offset or ridge p p at or very near the other end, thepurpose of which will be hereinafter described.

The quadrant H has three notches, as shown. \Vhen the lock-lever is atone extreme of its movementviz., that shown in Fig. 2, which may beconsidered its normal position-the latch g engages the notch 7e, and theslidebar 0 is in a position in which its lug 6 will engage the notch eof the notched bar 13. The switch is thus locked in position. In orderto shift the switch, the lever E is moved from the position shown inFig. 2 to its intermediate or central position, in which position thelatch will engage the central notch in the quadrant. The effect of themovement of the lever E to this position is to shift the slide-bar C tothe intermediate position shown in Fig. 5, in which position both of itslugs c and fare out of engagement with the notched bar 13, and theswitch consequently is unlocked. The switch then by its appropriateMotion from the latch-lever is transmitted lever is shifted, whichmovement brings the notch f of the notched bar l3 opposite to and in thepath of movement of the lug f on the slide-bar G. Then the lock-lever Eis swung over to complete its stroke and to bring its latch g intoengagement with notch 76 in the quadrant, and this movement of the leverwill cause the slide-bar to move in a direction to bring its lug fintoengagement with the notch f of the notched bar I thus locking the switchin its shifted position.

The machine shown in Fig. 2 is supposed to be supplied with a link G,such as shown in Fig. '7. The link obtains one-half of its movement bythe unlatehing of the lever E before it begins its stroke and by thelatching of said lever at the opposite extreme of its stroke. Forinstance, before the leverE can be moved from the position in which itis shown in Fig. 2 it must be unlatched. This is effected by pressingthe latch-lever F toward the lever E. In so moving the latch-leverraises the latchrod 1 and the latter through the link'block 7t tilts thelink one-half of its stroke. This movement of the link-block causes thetappetj to move the appropriate distance to lock up everything in themachine except the switchlever to which the lock-lever pertains. Thelock-lever E is then swung over or reversed part way until it comes overthe notch k in the quadrant without imparting further movement to thelink. lVhen in this position, the recess 1) in the bottom edge of theslot in the link willbe a straight line passing through the center orpivots m asof the link and the lever E, respectively. \Vhen the latch greaches the centernoteh 7& of the quadrant, the link-block will beopposite and just over the recess 2), and the latch g is then permittedto drop into engagement with said center notch, the linkblock itdropping into the center recess 2) and holding the link steady in itshalf-way position. The lock-lever is also held firmly at half-stroke andcannot be disturbed accidentally during the operation of theswitch-lever, which is reversed while the lock-lever is at rest athalf-stroke. After the switch-lever has been reversed the lock-lever Eis again taken hold of and fully reversed, its link block 7t beinglifted out of the recess 1) by the same movement of the latch-lever androd which disengages the latch g from the central quadrant-notch 70During this movement of the lock-lever the link-block traverses the slotin the link without actuating the latter, but after the lock-lever isfully reversed then the descent of the latchinto engagement with thequadrant-notch 7t", occasioned by the spring .9, will cause thelink-block h to complete its stroke. In this concluding halfstroke ofthe link and the tappetj, to which it is connected,the tappet willmaintain locked all conflicting levers, but will release these whichcontrol, for example, the signals which govern the right of way over theswitch just reversed. The same sequence of operation takes place whenthe lever is thrown over IIO from reversed to normal position. In thisway I am enabled tosuccessfully handle and control a double-plungerfacing-point switchlock from a mechanical interlocking machine withpreliminary locking. The link shown in Figs. 2 and 7, While designedspecially to be used with a lever handling the doubleplungerfacing-point lock in the manner hereinbefore described, can also be usedwithout change in connection with a two-position signal-lever.

To adapt the link for use in connection with a three-positionsignal-lever, the offsets or cam-ridges 19 and the recess 19 should beadded, the-cam-ridges being located at the end of the slot which isoccupied by the linkblock h when the lever is in normal position and therecess pin the lower edge of the slot being at the opposite or reverseend of the slot.

The cam-ridges or offsets p p are provided, because it is necessary,with a three-position signal that the link should make its full strokeat the outset of the movement from normal to reverse. The raising of thelink-block, due to the lifting of the latch-rod at the time the lever isbeing unlatched, will impart half of the stroke to the link and theother half is imparted to it by the link-block at the outset of themovement of the lever,

being brought into contact with and traveling over the upper cam-ridgeor offset 11 During the remainder of the stroke of the lever thelink-block traverses the slot in the ter.

' the recess go. If caution-signal is to be given, the lever is stoppedat the central notch k but if a safety-signal is to be given the leveris fully reversed. The cam-ridgeor offset 19 is the one which operatesto give one-half stroke to the link when the lever is being returnedfrom reverse to normal position. It will be noted that the lever must bebrought very near to its normal position before the link is operated atall. The result, as I find from actual practice, is that the signal isset facing-point switch-lock, and the lever and connections foroperating the same, of the latch -lever carried by said lock lever,thelatch, latch-rod and link-block, the quadrant, the tappet, and thepivoted slotted link, connected to the tappet, and engaging thelinkblockand provided in the lower edge of its slot with an intermediaterecess located as described to accomodate the link-block, when the latchis dropped into the intermediate notchof the quadrant, substantially asand for the purposes hereinbefore set forth.

2. The slotted link or rocker, provided with the offsets or cam-ridges p19 and the intermediate recess 19, and the end recess 10, substantiallyas and for the purposes hereinbefore set forth.

In testimonywhereof I have hereunto set my hand this 16th day of April,1898.

JOHN W. THOMAS, JR. Witnesses:

R. T.- SAUNDERS,

THOS. A. OLARKSON.

